Casey et al's U.S. Pat. No. 4,452,973 (1984) teaches the use of poly(glycolide)-PEO-poly(glycolide) ABA polymers as absorbable surgical articles.
Churchill et al's U.S. Pat. No. 4,526,938 (1985) teaches the use of ABA triblock polymers wherein the middle block is polyethylene oxide (PEO) and the end blocks are generally polylactic acid or polyglycolic acid as matrices for the controlled release of drugs.